Petroleum resins

ABSTRACT

In a process in which a C5 fraction from a cracked naphtha or gas oil is polymerised with the help of a Friedel-Crafts catalyst to produce a petroleum resin, the C5 fraction is first heated to a temperature of 160* to 250*C for a period of up to 5 hours and is then held at a temperature in the range 100* to 160*C for a further period of up to 5 hours.

United States Patent [191 Younger PETROLEUM RESINS [75] Inventor: DonaldAnthony Younger,

Stockton-on-Tees, England [73] Assignee: Imperial Chemical IndustriesLimited, London, England [22] Filed: Dec. 1, 1972 [21] Appl. No.:311,152

[30] Foreign Application Priority Data Dec. 15, 1971 Great Britain58225/71 [52] US. Cl 260/82, 260/33.6 PQ

[51] Int. Cl. C08f 15/04, C08f 15/42 [58] Field of Search 260/82 56]References Cited UNITED STATES PATENTS 2,750,359 6/1956 Hamner et a1.260/82 June 18, 1974 2,775,576 12/1956 Hamner et al. 260/82 2,817,64712/1957 Habeshaw et a1 260/82 3,709,854 l/1973 Hepworth et a1. 260/82Primary Examiner-Harry Wong, Jr.

Attorney, Agent, or Firm -Cushman Dabry &

Cushman [57] ABSTRACT 10 Claims, 1 Drawing Figure PETROLEUM RESINS Thisinvention relates to the production of petroleum resins.

ln our co-pending U.S. Patent application Ser. No. 177,113, now U.S.Pat. No. 3,709,854, we have described and claimed a process for theproduction of a hydrocarbon feedstock suitable for the production of apetroleum resin and also a process for the production of such a resin.1n the production of the hydrocarbon feedstock a C stream distilled froma cracked naphtha or gas oil is preheated before conversion to the resinby heating it to a temperature of at-least 160C for a period of up to 5hours. Preferably the C stream is heated to a temperature in the range160 to 200C and the time of heating is suitably 0.05 to 1.5 hours. It isalso disclosed in our copending application that the preheating of the Cfeedstock may be carried out in a continuous or batchwise manner. Thepresent invention is particularly applicable to the continuous processand provides a means whereby the I concentration of monocyclopentadienein the feed to thepolymerisation is kept as low as possible.

According to the present invention a C stream distilled from a crackednaphtha or gas oil is preheated'before conversion to the resin to atemperature of at least 160C fora period of up to 5 hours, and is thenheld at a temperature between 100 and 160C for a further period of up to5 hours.

Preferably the C stream is preheated to a temperature in the range 160to 250C, more preferably 160 to 200C.

Preferably the C stream is held at a temperature of between 100 and 160Cfor 0.05 to 1.5 hours and preferably the temperature is between 130 and150C. The desired temperature may be achi'eved isothermally or adiabaticconditions may be applied in which case the temperature may vary over agiven period of time within the range specified. At temperatures between100 and 160C the monocyclopentadiene which is present at thetemperatures .above 160C dimerises to dicyclopentadiene.

The C stream is derived from a thermally or steam cracked naphtha or gasoil and-typically boils in the range to 80C. It may contain thefollowing hydrocarbons: isoprene, cis and trans piperylene,npentane,'isopentane, pentene-l, cyclopentadiene, dicyclopentadiene,trans-pentene-2, 2-methylbutene-2, cyclopentene, cyclopentane andbenzene. In addition some C hydrocarbons may also be present. If desiredthis C stream may be further refined before being used in the process ofthe present invention, e.g. the isoprene may be removed by distillationand/or the monocyclopentadiene may be dimerised by heating at atemperature of 100 to 160C, e.g. at 120C, preferably for up to 5 hours,more preferably for 0.05 to 1.5 hours. Although the monocyclopentadienecontent of the C stream may be reduced by this means the followingtemperature rise above 160C tends to convert some of the dimer back tothe monomer. If the C stream is cooled directly from the temperatureabove 160C the C stream retains the increased concentration of themonocyclopentadiene and gives an inferior resin. By means of the presentinvention the concentration of monomer is once more reduced.

It is preferred to carry out the heat soaking stages continuously andthis may conveniently be effected in 2 tubular reactors in which thefeedstock passes through a tube, the residence time being that requiredfor the specific heat soak to take place. Each tube may be maintained atthe desired temperature, i.e. the conditions are isothermal or thesystem may be maintained under adiabatic conditions in which the heatgenerated by the reactions taking place may be used to obtain atemperature rise or to maintain a desired temperature. For example thefirst stage may be adiabatic with the temperature rising from to 180C,the second may be isothermal at 180C, and the third adiabatic at 100 to160C, the heat of dimerisation maintaining the temperature within thisrange,'e.g. at to C. 1f necessary cooling means may be'provided betweenstages to achieve the desired temperatures; When the C stream has beensubjected to the pretreatment in accordance with the present inventionit may be polymerised by meansof a catalyst to produce a resin. ThusFriedel Crafts catalysts are suitable, e.g. inorganic halides andinorganic strong acids. Inorganic halides are generally preferred andinclude halides of aluminium, iron, tin, boron, zinc, antimony andtitanium which may be used in conjunction with a hydrogen halide such ashydrogen chloride. For example,"

treatment with aluminium chloride preferably complexed with hydrogenchloride in an aromatic solvent such astoluene'or a xylene produces asolution from which the resin may be recovered. Preferably, however, theFriedel Crafts catalyst is used in an aromatic solvent which is abenzene which is liquid at the temperature of the polymerisation andwhich is substituted by at least one secondary or tertiary alkyl groupor by a cycloalkyl group, e.g. tert butyl benzene, p-cymene, p-isobutyltoluene, p-ethyl-tert amyl benzene or, in particular, cumene. Suchcatalysts are described in our copending British Patent Application No.5097/71; (equivalent Belgian Patent No. 779,454) a complex of aluminiumchloride, cumene and hydrogen chloride being preferred. Thepolymerisation of the C feedstock is preferably carried out at atemperature of 100 to-+200C, more preferably 50 to 100C underatmospheric pressure or a positive pressure, e.g. up to 700 p.s.i.g.,using a catalyst concentration of 0.05 to 5 percent, preferably 0.5 to1.5 percent by weight of the C 'stream. The catalyst is'finally brokendown and removed from the polymer by treatment, for example withalcoholic ammonia, aqueous alkali or aqueous alcohol followed by one ormore washes with water and,

' optionally, a steam distillation to remove residual monomers. Suitablealcohols are alkanols containing one to four carbon atoms, e.g.isopropanol and suitable alkalis are the alkali metal hydroxides such assodium hydroxide.

The polymerisation is preferably carried out continuously morepreferably by passage through a plurality of alternating polymerisationand cooling zones in which catalyst is added to each polymerisationzone. As the polymerisation is exothermic the temperature risesadiabatically in each polymerisation zone only to drop in the nextcooling zone preparatory to further polymerisation in the subsequentpolymerization zone. For most practical purposes the cooling zones maybe water cooled. The polymerisation and cooling zones may comprise anyvessels in which the desired processes can take place but tubularreactors are particularly suitable. In this case the preheated Cfeedstock together with catalyst passes through a tube in which itsresidence time is predetermined and through which the temperature risesdue to the heat of polymerisation. The next tube is cooled and theresidence time of the hydrocarbon is such that the required drop intemperature takes place during the passage of the hydrocarbon along thetube. The following tubular reactor is a polymerisation zone andadditional catalyst is introduced into the hydrocarbon feed. There maysuitably be two to eight pairs of such polymerisation and cooling zones,particularly three to five pairs. The amount of catalyst added overallis shared between the various polymerisation zones so as to achieveapproximately the same temperature rise and hence the same conversion ineach zone. I

The removal of the catalyst and the final washing of the polymer mayalso be carried out continuously, e.g. in aseries of mixers andsettlers. The polymer is finally stripped of residual C streamhydrocarbons, e.g. by a steam distillation, and is then ready for use.

The invention will now be further described with reference to theattached block diagram.

A C stream comprising isoprene, cisand transpiperylene, n-pentane,isopentane, pentene-l, cyclopentadiene, dicyclopentadiene,trans-pentene-2, 2- methylbutene-2, cyclopentene, cyclopentane andbenzene is stored in storage tank 1 from which it is fed continuously tothree tubular reactors 2, 3 and 4 in series. In the first reactor thetemperature of the C stream is allowed to rise adiabatically from 120Cto 180C as the exothermic dimerisation of the cyclopentadiene 20 for arepeat of the isopropanol/water washing process, the isopropanol/waterbeing fed in through line 21 and the spent wash liquor being removed vialine 22. A third wash with water alone takes place in mixer 23 andsettler 24, the water being fed in through line 25 and removed from themixer via line 26. The washed polymer solution is held in a storage tank27 from which it is fed to a final steam distillation unit 28 from thebase of which is recovered molten resin which is solidified in, forexample, pastillated form while the distillate comprising water andunreacted hydrocarbons is sent for recovery.

EXAMPLE 1 p.s.i.g.

EXAMPLES 2 TO 7 The procedure followed in Example 1 was repeated inExamples 2 to 7 using C streams with different contents ofmonocyclopentadiene. The results were as follows:

EXAMPLE 2 3 4 S 6 7 8 Initial monocyclopcntadicnc ('71 wt.) 15.7 13.913.1 12.4 10.5 10.3 9.11 Temp. of first heat soak (C) 180 1110 180 180180 170 160 Time of first heat soak (mins) 32 36 I2 18 411 48Monocyclopentadiene content after first heat soak (71 wt.) 2.0 2.1 1.62.1 2.0 1.6 1.4 Temp. of second heat soak (C) 150 150 150 150 140 140140 Time of second heat soak (mins.) 64 48 48 48 48 48 40 Finalmonocyclopentadiene. content (7: wt.) 1.0 0.3 1.0 1.0 0.9 1.0 0.9

7 EXAMPLE 8 takes place and is then held at this temperature in thesecond reactor. After leaving the second reactor the temperature of thestream is decreased to 135C and is then held at this temperature in thethird reactor. The residence time of the C stream is each reactor is '5,20 and 40 minutes respectively. After passing through the third reactorthe hydrocarbon stream is cooled to 60C in water cooler 5 and is thenfed continuously to a series of tubular polymerisation reactors 6, 7, 8and .9 interposed with water coolers 10, ll, 12 and 13 respectively.Catalyst is fed from a storage tank 14 to each polymerisation reactor.The catalyst is a liquid complex of aluminium chloride, hydrogenchloride and cumene and is fed to the four polymerisation reactors insuch amounts as to give the same temperature rise in each reactor. Thetemperature of the hydrocarbon stream rises in each reactor to 90 to100C and is then reduced to 60C in each subsequent cooler. Residencetime in each reactor is approximately 3 minutes. After leaving the lastcooler 13 the polymerised product is mixed with 10 percent of its weightof a 1:1 mixture of water and isopropanol from line 15 in mixer 16 andthen allowed to settle in settler 17. The isopropanol/- water/aluminiumchloride is removed from the settler by line 18 for recovery of theisopropanol while the polymer solution is pumped to a mixer 19 andsettler 2.5 Kilograms of a C stream was heated to a temperature of 180Cin a 5-litre autoclave and washeld at this temperature for 25 minutes.The temperature in the autoclave was then allowed to fall to 150C andwas held at this temperature for a further 40 minutes. This resulted ina polymerisation feedstock of the following compositioni3-methylbutene-l (0.4% wt.), pentene-l (2.8% wt.), 2-methy1butene-1(5.1% wt.). pentene-2 (1.7% wt.) isoprene 12.9% wt.), 2-methylbutene-2(2.8% wt.). trans-piperylene (5.6% wt.), cis-piperylene (3.3% wt.).cyclopentene (3.1% wt.). dicyclopentadiene (13.3% wt. mixed dimers ofisoprene, piperylem: and cyclopentadiene (5.7% wt.).

the temperature decreased to C. 10 m1. of catalyst was then added whenthe temperature rose again to 107C. The reaction mixture was againcooled to 60C and again 10 mls. of catalyst added. Following furthercooling to 60C the final 20 mls. of catalyst were introduced and after 2minutes reaction the mixture was cooled down to ambient temperature. Intotal 68 mls. of catalyst complex were added which contained a total of19.8 grams of aluminium chloride.

The resin solution resulting from the polymerisation was stirred gentlywith a 1:1 mixture by volume of isopropanol and water (300 mls.) andallowed to settle. The resin layer was separated and the processrepeated. Finally the resin solution was washed'with two separateamounts of water (300 mls. each). The resin was isolated bydistillation, firstly at atmospheric pressure with a sidearm take-offand boiler temperature up to 180C to remove unpolymerised constituentsof the C stream and lastly at 50 mm. pressure and boiler temperature200C.

The yield of resin was 38% by weight based on the weight of C streamused and was found to have a Gardner colour of l 1 (50% solution intoluene), a softening point (ball and ring) of 108C and melt viscosity4.1 poise at 200C and 78.4 poise at 130C.

1 claim: v

1. In a process for the production of a petroleum resin soluble inhydrocarbon solvents by polymerising in the presence of a Friedel-Craftscatalyst a C stream which has been distilled from a cracked naphtha orgas oil and which has been heated to a temperature in the range of 160to 250C for a'period of up to five hours before carrying out thepolymerisation the improvement whereby after heating to in the range of160C to 250C but before the polymerisation, the C stream is cooled toand held at a temperature between 100 and 160C for a further period of0.05 up to 5 hours.

2. The process of claim 1 in whichv the C stream is held at atemperature of between 100 and 160C for a period of 0.05 to 1.5 hours.

3. The process of claim 1 in'which the C stream is held at a temperatureof between 130 and 150C.

4. The process of claim 1 in which monocyclopentadiene is firstdimerised by heating the C stream at a temperature of 100 to 160C for upto 5 hours.

5. The process of claim 1 in which the heating stages are carriedout intubular reactors.

6. The process of claim 1 in which cooling means are 7 provided betweenthe heating stages.

nally broken down and removed from the polymer by treatment withalcoholic ammonia, aqueous alkali or aqueous alcohol.

10. The process of claim 1 in which a C stream boiling in the range 10to 80C is,

a. heated to a temperature in the range 100 to 160C for 0.05 to 1.5hours to dimerise monocyclopentadiene,

b. is then heated at 160 to 220C for a period of 0.05 i

to 1.5 hours, c. is next held at 130 to 150C for 0.05 to 1.5 hours,

d. is contacted with a catalyst comprising aluminium cumene,

e. is treated with aqueous sodium hydroxide or aqueous isopropanol, and

f. is. water washed and separated from residual C hydrocarbons bydistillation to yield a petroleum resin.

chloride, hydrogen chloride and toluene, xylene or

2. The process of claim 1 in which the C5 stream is held at atemperature of between 100* and 160*C for a period of 0.05 to 1.5 hours.3. The process of claim 1 in which the C5 stream is held at atemperature of between 130* and 150*C.
 4. The process of claim 1 inwhich monocyclopentadiene is first dimerised by heating the C5 stream ata temperature of 100* to 160*C for up to 5 hours.
 5. The process ofclaim 1 in which the heating stages are carried out in tubular reactors.6. The process of claim 1 in which cooling means are provided betweenthe heating stages.
 7. The process of claim 1 in which theFriedel-Crafts catalyst is an inorganic halide selected from the groupconsisting of halides of aluminium, iron, tin, boron, zinc, antimony, ortitanium.
 8. The process of claim 1 in which the polymerisation iscarried out by passage through a plurality of alternating polymerisationand cooling zones in which catalyst is added to each polymerisationzone.
 9. The process of claim 1 in which the catalyst is finally brokendown and removed from the polymer by treatment with alcoholic ammonia,aqueous alkali or aqueous alcohol.
 10. The process of claim 1 in which aC5 stream boiling in the range 10* to 80*C is, a. heated to atemperature in the range 100* to 160*C for 0.05 to 1.5 hours to dimerisemonocyclopentadiene, b. is then heated at 160* to 220*C for a period of0.05 to 1.5 hours, c. is next held at 130* to 150*C for 0.05 to 1.5hours, d. is contacted with a catalyst comprising aluminium chloride,hydrogen chloride and toluene, xylene or cumene, e. is treated withaqueous sodium hydroxide or aqueous isopropanol, and f. is water washedand separated from residual C5 hydrocarbons by distillation to yield apetroleum resin.